U.S. patent number 4,817,483 [Application Number 07/071,088] was granted by the patent office on 1989-04-04 for electrically powered dispenser for rolled sheet material having a rotary blade cutter.
Invention is credited to Joseph M. Armbruster.
United States Patent |
4,817,483 |
Armbruster |
April 4, 1989 |
Electrically powered dispenser for rolled sheet material having a
rotary blade cutter
Abstract
A dispenser for sheet material supplied in a spirally wound roll
such as paper towels, or the like, in which the paper web is fed
from the supply roll by an electrically driven feed roller and an
opposed spring biased feed roller follower for gripping and feeding
the paper web through a discharge slot in a housing. A
reciprocating cutter assembly is mounted adjacent the discharge
slot and feed roller which includes a carriage with an electrically
driven rotary cutter blade mounted thereon with the carriage being
guided by a guide structure and propelled transversely of the path
of the paper web by an electrically powered cable and drum
arrangement.
Inventors: |
Armbruster; Joseph M.
(Lighthouse Point, FL) |
Family
ID: |
22099173 |
Appl.
No.: |
07/071,088 |
Filed: |
July 8, 1987 |
Current U.S.
Class: |
83/488; 83/614;
83/649 |
Current CPC
Class: |
A47K
10/36 (20130101); B26D 1/185 (20130101); Y10T
83/896 (20150401); Y10T 83/778 (20150401); Y10T
83/8822 (20150401) |
Current International
Class: |
A47K
10/24 (20060101); A47K 10/36 (20060101); B65H
075/32 () |
Field of
Search: |
;83/205,487,488,649,614,650,455,456 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Yost; Frank T.
Assistant Examiner: Jones; Eugenia A.
Attorney, Agent or Firm: Fleit, Jacobson, Cohn &
Price
Claims
What is claimed as new is as follows:
1. A dispenser for rolled sheet material comprising a hollow
housing, means in the housing to rotatably support a roll of sheet
material, said housing including a discharge slot through which a
web of sheet material can be discharged, means in said housing to
move a web of material through the discharge slot, and means in
said housing for cutting the web of material adjacent to but spaced
from the discharge slot, said cutting means comprising a carriage
movable transversely of the web of material, a motor mounted on the
carriage and including an output shaft, a rotary circular cutting
blade mounted on the output shaft with the periphery of the blade
engaging and cutting the web of material when the carriage is moved
transversely of the path of movement of the web of material, said
means in the housing to move a web of material including a feed
roller engaging one surface of the web of material, a feed roller
follower engaging the opposite surface of the web of material in
opposed relation to the feed roller with the feed roller follower
being a plate-like member having an upwardly offset portion
engaging the web of material, said follower being pivotally mounted
and spring biased toward the feed roller, a feed roller drive motor
connected to the feed roller through a reduction drive train, and a
feed roller wiper engaged with the periphery of the feed roller in
spaced relation to the follower to prevent the web of material from
wrapping around the feed roller.
2. The dispenser as defined in claim 1 wherein said carriage
includes a body, stationary guide rail means mounted in said
housing supporting and guiding the carriage body for reciprocatory
movement transversely of the path of movement of the web of
material, a carriage drive motor and carriage transport means
connected with the carriage drive motor and the carriage for moving
the carriage transversely.
3. The dispenser as defined in claim 2 wherein said carriage drive
motor is reversable to move the carriage in a reciprocatory manner
transversely of the path of movement of the web of material, said
carriage transport means including a rotary drum driven by the
carriage drive motor, a cable wound on and attached to the drum,
idler pulleys mounted adjacent the ends of the guide rail means in
alignment with the carriage and drum with the cable entrained over
the pulleys and having a mid-portion connected with the carriage
for moving the carriage upon actuation of the carriage drive
motor.
4. The dispenser as defined in claim 1 wherein said feed roller is
rotatably supported in spaced parallel relation to the roll of
sheet material in the housing and includes a resilient coating on
the exterior surface thereof with axially spaced grooves being
formed in the resilient coating, said wiper including a plurality
of fingers inserted into the grooves between the surface of the web
of material engaged by the feed roller and the inner surface of the
grooves, said wiper and fingers being disposed adjacent the feed
roller and between the feed roller and discharge slot with the
fingers extending into the grooves from the discharge side of the
roller to prevent the web of material from wrapping around the feed
roller.
5. The dispenser as defined in claim 4 wherein said means to
support a roll of sheet material including a pair of hollow
spindles telescoped into the end portions of a web core, said feed
roller drive motor being partially received in one of the hollow
spindles for compact construction.
6. The dispenser as defined in claim 2 wherein said guide rail
means for the carriage includes a single guide rail having a
generally T-shaped flange configuration along its upper edge with
the carriage including a correspondingly shaped recess to provide
accurate and controlled reciprocation of the carriage.
7. The dispenser as defined in claim 2 wherein said guide rail
means includes at least one guide rail having a non-circular
cross-sectional configuration for guiding and stabilizing the
carriage.
8. The dispenser as defined in claim 2 wherein said guide rail
means includes a pair of spaced rails for guiding and stabilizing
the carriage.
9. The dispenser as defined in claim 2 wherein said blade motor and
blade are interconnected to form a sub-assembly with the motor
including projecting contacts for telescopic insertion into a motor
receiving socket having female contacts therein to enable
replacement of the motor and blade as a sub-assembly.
10. The dispenser as defined in claim 1 together with a vertically
reciprocating safety door mounted in the housing inwardly of the
discharge slot for closing the discharge slot when the rotary
clutter blade is moved transversely of the path of movement of the
web of material thereby preventing access to the rotary cutter
blade when it is moving transversely between the ends of the
slot.
11. A dispenser for sheet material spirally wound into a roll
comprising a housing having a discharge slot, means interiorly of
the housing to rotatably support a roll of sheet material with the
free end of the sheet material being extendable outwardly through
the discharge slot, means oriented internally of the housing for
feeding sheet material from the supply roll through the discharge
slot and means in said housing to cut the sheet material
transversely between the feed means and discharge slot by which a
predetermined length of sheet material may be severed, said feed
means including a driven feed roller positioned parallel to the
discharge slot and roll of sheet material with the sheet material
engaging a substantial circumferential portion of the feed roller
as the sheet material passes under the feed roller, said feed
roller including a resilient peripheral surface for gripping
engagement with the sheet material, a feed roller follower
positioned below the feed roller and engaging the sheet material in
opposed relation to surface of the feed roller, said follower being
in the form of a pivotally mounted plate-like member having an
upwardly offset portion engaging the undersurface of the sheet
material at a transverse area generally aligned with the rotational
axis of the feed roller with the follower and feed roller
cooperating to frictionally grip the sheet material for pulling it
off of the supply roll and discharging it through the discharge
slot, a feed roller wiper disposed above the sheet material and
oriented between the feed roller and discharge slot, said feed
roller including peripheral grooves and said wiper including
fingers extending downwardly under the feed roller and curving
upwardly and terminating in tapered free ends above the point of
engagement of the sheet material with the feed roller as it
approaches the feed roller with the fingers being received in the
grooves in the feed roller to assure that the sheet material will
not wrap around the feed roller, said wiper including a downwardly
facing generally horizontal surface extending from the feed roller
toward the discharge slot to guide sheet material into the
discharge slot, said means for cutting the sheet material including
a carriage in the housing, means supporting the carriage for
reciprocatory movement parallel to the discharge slot and adjacent
thereto and between the discharge slot and wiper, a cutter blade
mounted on the carriage in underlying relation to the sheet of
material for cutting the sheet of material from the undersurface
thereof, means moving the carriage in a reciprocating manner in
relation to the housing and discharge slot, said cutter blade being
a circular blade, a motor on the carriage having an output shaft
connected to the circular blade for driving the blade independently
of the means to move the carriage, said housing including a movable
closure door for the discharge slot during the cutting operation to
prevent accidental contact with the rotary blade.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a dispenser for sheet
material supplied in a spirally wound roll such as paper towels, or
the like, in which the paper web is fed from the supply roll by an
electrically driven feed roller and an opposed spring biased feed
roller follower for gripping and feeding the paper web through a
discharge slot in a housing. A reciprocating cutter assembly is
mounted adjacent the discharge slot and feed roller which includes
a carriage with an electrically driven rotary cutter blade mounted
thereon with the carriage being guided by a guide structure and
propelled transversely of the path of the paper web by an
electrically powered cable and drum arrangement.
2. Information Disclosure Statement
Paper web material such as paper towels and the like have been
dispensed from a supply roll by using various structural
arrangements. Usually the supply roll is rotatably supported so
that when tension is exerted on the free end of the paper web, the
paper web can be pulled outwardly with the supply roll rotating on
a support structure so that a desired quantity, either fixed length
or variable length, may be separated from the paper web for use.
While various types of power operated dispensing devices are known,
they are not the same as or equivalent to the structure disclosed
in this application. A separate information disclosure statement
will be filed.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an electrically
operated dispenser for paper towels or other sheet material in
which a rotary cutter blade mounted on a carriage is moved
transversely of the path of movement of the paper web for cutting
the paper web at a desired point with the rotary cutter blade being
independently powered by an electric motor and the carriage being
reciprocated transversely of the path of movement of the paper web
by an independent electric motor, guide rail assembly, cable and
cable drum transport assembly.
Another object of the invention is to provide a dispenser in
accordance with the preceding object in which the paper web is
supplied in a spiral roll with the paper web extending between a
feed roller and an opposed spring biased feed roller follower with
the feed roller being independently powered for feeding a paper web
through a discharge slot with the rotary cutter blade and its
associated structure being disposed interiorly of a housing
adjacent the discharge slot and feed roller.
A further object of the invention is to provide a paper web
dispenser with rotary blade cutting assembly in which the feed
roller is powered by an electric motor through a gear train in
which the electric motor is housed in a hollow spool that
telescopes into the core tube which supports one end of the paper
roll to provide a compact structure.
Still another object of the invention is to provide a paper web
dispenser in accordance with the preceding objects in which the
driven feed roller is provided with a coating of rubber or similar
resilient material with a plurality of axially spaced grooves
therein receiving a blade or wiper structure conforming in shape
therewith to preclude the paper web from wrapping around the feed
roller thereby assuring that the paper web will be discharged
through a discharge slot in a housing so that the rotary cutter
blade can effectively cut the paper web at a desired point with the
components of the assembly being controlled in a manner to provide
proper sequential operation of the components.
These together with other objects and advantages which will become
subsequently apparent reside in the details of construction and
operation as more fully hereinafter described and claimed,
reference being had to the accompanying drawings forming a part
hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the dispenser of the present
invention.
FIG. 2 is a transverse sectional view of the dispenser illustrating
the structure and relationship of the components.
FIG. 3 is a longitudinal sectional view of the dispenser.
FIG. 4 is a fragmental elevational view of the paper roll spools
and their association with the paper roll together with the
association with a feed motor therewith.
FIG. 5 is a schematic view of the gear-type drive train between the
feed motor and feed roller.
FIG. 6 is a schematic view of a belt-type drive train between the
feed motor and feed roller.
FIG. 7 is a schematic view illustrating structural details of the
rotary blade and motor.
FIG. 8 is a fragmental view of a different type of motor and
assembly.
FIG. 9 is a fragmental view of another motor and blade
structure.
FIG. 10 illustrates alternative guide rail structures for the
carriage.
FIG. 11 is a detailed side elevational view of the feed roller with
portions broken away.
FIG. 12 is a sectional view of the roller wiper and feed roller
structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The dispenser of the present invention is generally designated by
reference numeral 20 and includes a housing 22 having a generally
flat, horizontal bottom wall 24 and a hollow upper wall 26 that
includes a curved upper portion which may be oval shaped in
configuration, symmetrical or any desired shape with the housing
including end walls 28 and 30. The bottom wall 24 is provided with
supporting pads or feet 32 adjacent the corners thereof by which
the dispenser may be supported on a supporting surface such as a
countertop in the kitchen or the like. The dispenser also may be
constructed so that it can be supported in suspended relation by
brackets under a kitchen cabinet or other supporting structures.
The hollow interior of the housing 26 receives a roll of spirally
wound sheet material 34 such as paper toweling, aluminum foil,
plastic wrap, toilet tissue or other similar material which is
provided with a tubular central core 36 of cardboard or similar
material. The web of sheet material 34 may or may not be provided
with tear off lines with the size and configuration of the housing
22 being sufficient to enable a full roll of sheet material 34 to
be positioned therein through an open end of the housing formed by
the end wall 30 being pivotally connected to the end of the housing
by a hinge structure 38. The specific construction of the hinge 38
and latch structure to secure the end wall 30 in closed position
enables the roll of sheet material to be easily inserted and
replaced when desired.
The interior of the housing 22 includes a support in the form of a
wall or chassis 42 having a centrally disposed projecting, hollow
spool 44 which partially telescopes into the hollow core 36 of a
roll of sheet material 34. Also, the pivotal end wall 30 covers a
pivotal support member 46 that is hingedly connected to the bottom
wall 24 by a spring hinge 48 with this member also being provided
with a hollow spindle 50 in engagement with the opposite end of the
core 36 of the roll of web material 24 so that the roll of web
material will have a degree of frictional resistance to free
rotational movement. As illustrated in FIG. 4, the chassis or wall
42 and the paper supporting spool 44 partially receives a paper
feed motor 52 having an output pinion gear 54 in meshing engagement
with a gear train or other drive train generally designated by
numeral 56 as illustrated in FIG. 3. Thus, by pivoting the end wall
30 and the support member 46, a supply roll of paper web material
34 may be inserted into the dispenser.
The drive train 56 reduces the output speed from the motor for
driving a feed roller 58 at a reduced speed. The feed roller is
oriented in parallel relation to the supply roll of paper web
material 34 as illustrated in FIG. 2 with the rotational center of
the roller 58 being disposed horizontally below the rotational
center of the roll of paper web material 34 so that the paper
coming off of the paper roll will extend downwardly and under the
feed roller 58 which has a wiper structure 60 associated therewith
and a roller follower 62 associated therewith with the follower
being located below the roller 58 and the roller wiper 60 being
located against the surface of the roller 58 remote from the paper
web material 34. With this construction, the paper web 34 will be
discharged through a discharge slot 64 in the housing 22 with the
discharge slot 64 being spaced upwardly from the bottom wall 24 as
illustrated in FIG. 2.
Mounted below the feed roller 58 is a carriage 66 mounted on a
carriage guide or transport rail 68 for lateral or transverse
movement in relation to the housing with these components being
oriented so that a rotary circular cutter blade 70 mounted on the
carriage 66 will cut the paper web 34 immediately inwardly of the
discharge slot 64 when the feed roller 58 is stopped and the rotary
blade 70 is driven and the carriage 66 moved transversely of the
path of movement of the paper web. A carriage drive motor 72
laterally reciprocates the carriage 66 through a drum and cable
drive assembly 74 and the rotary cutter blade 70 is powered by an
electric motor 76 secured to the carriage 66.
The roller follower 62 includes a pair of arms 78 pivotally
supported by pivot pins 80. The arms 78 are interconnected by a
plate-like structure having an upwardly offset portion 82 in
opposed relation to the lowermost periphery of the feed roller 58
as illustrated in FIG. 2 with the outer end of the plate being down
turned at 84 so that the paper web will be frictionally and
resiliently gripped between the feed roller 58 and the feed roller
follower 62 with a tension spring 86 connected to each of the arms
for biasing the roller follower 62 towards the feed roller 58.
The feed roller 58 includes a roller shaft 88 having a coating of
rubber or similar resilient material 90 thereon with grooves 92
being formed in the rubber coating throughout the length of the
roller with the grooves being relatively narrow as compared to the
rubber coating between the grooves. The ends of the shaft 88 are
journalled in bearing structures 94 in support members 42 and 46.
The roller wiper 60 includes a vertical blade structure 96 which
includes a laterally extending lower end 98 that includes extending
tines 100 which are received in the grooves 92 and extend for a
substantial portion of the bottom periphery of the roller shaft
with the terminal end of the tines 100 being tapered as at 102 and
generally being in horizontal alignment with the rotational axis of
the roller shaft 88 as illustrated in FIG. 12 so that the paper web
34 passing under the feed roller 58 will contact the outer
periphery of the rubber coating 90 with the tines or fingers
assuring that the paper web will not wrap around the roller shaft
88 thereby preventing any possibility of the dispenser being jammed
due to the paper web wrapping around the roller.
The carriage guide or transport rail 68 has a transverse
configuration similar to an I-beam as illustrated in FIG. 2 and
also as illustrated in FIG. 10 with the bottom rail 104 being
secured to the bottom wall 24 by fasteners 106 and the upper flange
108 slidably receiving a correspondingly shaped recess 110 in the
carriage body 112 which includes a clamp sleeve or other suitable
mounting structure 114 for securing the blade motor 76 to the
carriage body 112. The carriage motor 76 includes an output shaft
116 supporting the circular blade 70 so that it moves transversely
between the discharge slot 64 and the roller wiper 60 as
illustrated in FIG. 2 with the upper periphery of the rotary blade
70 being disposed above the top edge of the slot 64 to assure that
the paper web 34 will be cut when the carriage moves transversely
along the rail 68 from an at rest position to a position at the
other end of the rail. The carriage body 112 includes an extension
118 having the cable 120 of the drum and cable assembly 74
connected thereto with the cable being wound on and secured to a
drum 122 which is driven by a gear drive assembly 124 from the
carriage drive motor 72 secured to the bottom wall 24 by a suitable
bracket structure 126. The cable 120 is entrained over pulleys 128
at each end of the guide rail and is connected to the extension 118
so that the reversable carriage drive motor 72 may reciprocate the
carriage and blade across the path of movement of the paper web. As
an alternative to the cable and drum carriage drive, a toothed
timing belt, drive gear and pulleys may be used which provides a
simplified structure. The blade motor 76 is supplied electrical
energy through a power cord 130 which lies along the surface of the
bottom wall in a manner similar to such power cords used in various
types of typewriter and computer printer carriages.
FIG. 5 illustrates the gear train 56 as involving a plurality of
meshed gears 132 between the paper feed motor 52 and the paper feed
roller 58 whereas FIG. 6 illustrates a drive train 56 which
includes a combination of a gear set 134 and a timing belt and
pulley drive 136 interconnecting the paper feed motor 52 and the
paper feed roller 58.
FIG. 7 illustrates the rotary cutter blade 70 and blade motor 76 in
which the output shaft 138 of a motor 76 extends through a hub 140
with a retaining ring 142 permanently securing the blade and hub
together so that the motor and blade assembly may be replaced as a
unit. In this construction, the motor includes a pair of contacts
or leads 144 projecting from the end thereof remote from the shaft
138 with the motor being telescoped into a socket 146 which has
female contacts 148 associated therewith to supply electrical
energy to the motor when the motor is plugged into the socket.
FIG. 8 illustrates another embodiment of the blade motor 76 in
which the output shaft 150 includes a hub 152 thereon with a
threaded extension 154 with the blade 70 being secured in place by
a washer and nut assembly 154 with the nut and hub including flats
for receiving a Y-shaped wrench or wrenches 156.
FIG. 9 illustrates another motor assembly including the motor 76
having an output shaft 158 having a threaded hub 160 with flats
frictionally pressed thereon with the hub 160 including a threaded
shaft 162 extending through the blade 70 with the washer and nut
assembly 164 securing the blade in position in the same manner as
FIG. 8.
FIG. 10 illustrates alternative guide rail structures including a
pair of parallel, spaced guide rails 166 which slidably support the
carriage in the same manner as the rail 68 and also a single rail
168 which is oval shaped in transverse configuration with it being
pointed out that various polygonal shapes may be employed so that
the rotational axis of the cutter blade 70 will remain
substantially horizontal with the blade being disposed
substantially vertical.
As illustrated in FIG. 1, the dispenser 20 is supplied with
electrical energy from a conventional cord 170 having a
conventional plug thereon and an arcuate actuating switch 172 is
mounted on the housing 22 adjacent the end thereof having the feed
roll motor associated therewith for actuation of the dispenser.
The rotary cutting blade 70 may vary in structural characteristics
but a circular blade having a diameter of approximately 2" and a
thickness ranging between 0.005" and 0.015" has been found
satisfactory and, as indicated, the blade may be connected to the
motor shaft in several different ways and the motor may be a
sub-assembly along with the blade that is plugged into a socket
arrangement. The carriage 66 slides on the guide rail structure
such as the beam configurations and arrangements illustrated in
FIG. 2 and in FIG. 10. The power cord 130 to the blade motor 76 is
a flexible flat or ribbon wire which is stored along the bottom of
the chassis and travels with the carriage as it traverses across
the paper web with the power cord arrangement being similar to
those used in typewriter carriages, computer printer carriages and
the like. The carriage drive motor gear drives the drum through a
reduction gear arrangement with the cable being fastened to the
drum and provided with turns around the drum, preferably four to
seven turns and then extends across the front of the machine and
around idler pulleys and back to and attached to the drum with the
carriage drive cable being fastened to the carriage as illustrated
in FIG. 2.
The paper roll is held in stored and aligned position by the spools
44 and 46 and the paper feed motor 52 is mounted partially inside
the spool 44 as illustrated in FIG. 4 and the output gear 54 on the
motor 52 meshes with the input gear of the drive train 56
regardless of whether the drive train is a gear train as
illustrated in FIG. 5 of a gear and timing belt drive train as
illustrated in FIG. 6. As illustrated, the paper holding spools 44
and 46 are smaller than the paper towel core 36 with one of the
spools being mounted on a spring loaded support member or arm 46
supported by the hinge 48 so that the support member or arm 46 can
be swung downwardly or outwardly when the end wall 30 is opened to
provide access for positioning the paper roll on the spool for
replacement of the paper roll when necessary. The panel or wall 42
has the spool 44 mounted thereon or integral therewith is larger
than the paper roll to help align a roll of paper towel onto the
spool 44. Both of the spools 44 and 50 have rounded inner ends to
facilitate guiding them into the paper towel core 36.
In order to operate the dispenser, the large switch actuator 172 on
the exterior of the housing is depressed. If the switch actuator
172 is only momentarily pushed inwardly or tapped, a predetermined
length of paper towel will be dispensed and cut. Otherwise, the
sheet of paper dispensed will be determined by the length of time
that the switch actuator 172 is depressed.
As soon as the switch actuator 172 is depressed, the blade motor 76
is energized thus rotating the blade to provide time for the blade
to build up speed as the paper is being dispensed so that when the
desired length of paper towel has been dispensed and the feed motor
stops, the blade motor carriage can be traversed across the paper
immediately thereby eliminating any need for time to build up RPM
by the blade. Also, as indicated, depression of the switch actuator
172 also actuates the feed motor 52 thus actuating the feed roller
58 with the length of the paper dispensed through the discharge
slot being determined by the manner of actuation of the switch
actuator 172.
When the carriage 66, motor 76 and blade 70 have traversed from an
initial at rest position all the way across the paper, a limit
switch will be actuated that sends a signal to a circuit
arrangement on a circuit board that reverses the carriage motor 72
to move the carriage back across the paper until it closes a limit
switch at its original position which stops the carriage in its
initial or ready position ready for paper to be dispensed again
when the actuator 172 is depressed.
As the paper feed motor 52 is actuated, paper 34 is fed between the
paper drive roller 58 and the roller follower 60 through the output
slot or paper exit opening 64. The paper is kept from jamming the
paper drive roller by the roller wiper 60 which has protrusions or
fingers 100 that contact the roller shaft 88 in the grooves or
slots 92 in the rubber coating 90 on the roller shaft 88. This
structure prevents the paper 34 from following the feed roller and
assuring that the paper will be guided through the exit opening
64.
As illustrated in FIG. 2, a safety door 174 may be associated with
the exit slot 64 to prevent injury from the cutting blade with the
door closing the slot 64 when being elevated and opening the slot
64 when lowered with the door being positioned between the rotary
blade 70 and the wall defining the lower edge of the slot. The
safety door 174 may be raised and lowered by a motor or solenoid
and controlled in a manner that when the door is open, the carriage
cannot travel across the path of movement of the paper. FIG. 2
shows the door in open position as paper is dispensed and when the
feed motor stops the door 174 will be moved to closed position
which permits clearance for the motor shaft and carriage assembly
to travel across the path of movement of the paper. Actuation of
the door may be accomplished by the use of a normally open switch
in series with the carriage motor so that the switch is closed when
the door closes the paper exit opening. Alternatively, a mechanical
interference structure may be employed so that when the safety door
is open, the carriage path is blocked by the door as shown in FIG.
2 since the door in FIG. 2 is lowered and blocks movement of the
motor shaft 116 thereby blocking movement of the carriage, motor
and rotary blade. A circuit board with control circuits associated
therein may be conveniently mounted interiorly of the housing with
the limit switches for the carriages also being conveniently
mounted in an adjustable manner to assure proper operation of these
components. Since these components are substantially conventional
in construction, the details thereof have not been illustrated.
The foregoing is considered as illustrative only of the principles
of the invention. Further since numerous modifications and changes
will readily occur to those skilled in the art, it is not desired
to limit the invention to the exact construction and operation
shown and described, and, accordingly, all suitable modifications
and equivalents may be resorted to, falling within the scope of the
invention.
* * * * *